1. Field of the Invention
The present invention relates to a receiving apparatus, and in particular to an apparatus and a method which are capable of receiving a streaming broadcast via a network.
2. Related Background Art
Conventionally, there is known an apparatus for receiving a digital television broadcast. In recent years, a streaming broadcast, which distributes digital broadcast data via a network, has been performed.
In the case of receiving and viewing the streaming broadcast, packet information of the streaming broadcast as shown in FIG. 1 composed of various target formats is separated from packet information of the network which is received through the network. Then, the packet information is reproduced by a player, which corresponds to the respective streaming broadcast formats, and viewed.
At this point, the packet information of the streaming broadcast is not collectively or continuously recorded on a storage device in a receiving apparatus for the purpose of contents protection for preventing illegal usage of the contents. However, in order to sequentially process independent image data, audio data, or header information for synchronization, which are included in the packet information of the streaming broadcast, received streaming data is temporarily buffered, and then the packet information is reproduced after decode processing and synchronization processing of each data are performed.
In addition, in this case, information necessary for reproduction is erased immediately at a point when reproduction of the packet information part of the streaming broadcast is completed, whereby a purpose of contents protection is also realized.
In this way, in audio-visual viewing of the streaming broadcast, even in the case in which packet information cannot be received continuously owing to an influence of a trouble on the network, an influence of server load on a sender side of the streaming broadcast, or an influence of a processing procedure or the like for reproduction, the influence is absorbed by buffering to some extent. As a result, as shown in FIG. 2, audio-visual viewing is not interrupted, although a buffering quantity fluctuates with time more or less, and stable audio-visual viewing and reproduction of the streaming broadcast are realized. As a reception system of a streaming broadcast of this type, one described in Japanese Patent Application Laid-Open No. 2001-359073 is known.
However, even in such a structure, owing to various unrecoverable troubles of the network to which the receiving apparatus is connected, an increase in server load caused by unexpected access of viewers, or the like, as shown in FIG. 3, the buffering quantity of the packet information of the streaming broadcast decreases, and the packet information of the streaming broadcast which should be reproduced on a real time basis runs out. As a result, the streaming broadcast under audio-visual viewing may be interrupted suddenly regardless of partitions of scenes.
In this case, audio-visual viewing is suddenly interrupted without any warning to a user and totally regardless of a plot of a story even if the streaming broadcast under audio-visual viewing is in an important introduction which leads a viewer into the world of a story, in a climax scene in the middle stage, or right in the middle of an unexpected twist in the final stage. As a result, amusement of the streaming broadcast for the viewer is lost.
A story such as a drama has been described above as an example of the streaming broadcast. However, news, a documentary, a musical program, or the like is the same in that amusement is lost owing to interruption of the streaming program in the middle of a piece of news or one tune.
As a result, since the viewer feels the program is not amusing, a provider of contents of the streaming broadcast and a streaming broadcasting station, and even the viewer suffer disadvantages, respectively.
In addition, even when the trouble on the network or the server load is solved, buffering of the streaming broadcast is restarted, and audio-visual viewing becomes possible, since the broadcast is restarted regardless of partitions of scenes as in the interruption of the streaming broadcast, continuity of the story is lost to confuse the viewer.